1. Technical Field
The present invention relates to a balloon catheter system, particularly to a balloon catheter system employed for a thermal therapy used for ablating, at appropriate temperatures, a source origin of arrhythmia, an unstable atherosclerotic lesion, proliferated smooth muscles which cause bronchial asthma, cancer tissues or the like.
2. Background Art
As a therapeutic modality for treating lesions such as the origin of arrhythmia, atherosclerosis or the like, using a balloon catheter system (e.g., refer to patent documents 1, 2), one has been known in which the tissue in contact with the balloon is subjected to thermal treatment. This balloon catheter system is equipped with a balloon provided with an electrode for delivery of radiofrequency current therein. A radiofrequency current is applied to the electrode for delivery of radiofrequency current and thereby an inside of the balloon is heated to raise a surface temperature of the balloon and then the tissue in contact with the balloon is directly ablated. A tissue depth ablated by the balloon (when the tissue temperature is at 45 degrees or more) is proportional to the surface temperature of the balloon and the delivery time of radiofrequency current and therefore it is of extreme importance to predict the surface temperature of the balloon (FIG. 6).